Speed-sensitive controlling device



Patented Feb. 19, 19124.

, narran stares nonna-fr F, METCALFE, AorrlaIE, PENNSYLVANIA, Assrcfnoa 'ro sxrnnna PATENT' Homme connai/mvv, or Earn, rnnnsvnvnmaj, CORPORATION or rmmsrr.-

VANIA. v

kSIPEED-SCITSJTIVE CONTROLLING DEVICE.

Application led October 27, 193.9. Serial 170.333,793.

To all whom t may concern.' ,Y

. Be it known that I, ROBERT F. METCALFF.,

a citizen of the United StateawreSiding at Erie, in the county "of Erie and State of Pennsylvania, have invented new and useful Improvements in Speed-Sensitive Controlling Devices, of which the following is a specification. l

The invention is particularly designed for controlling certain operations of motors which operations are not what are ordinarily termed a governing operation. The device broadly speaking, however, is capable of acting as a speed governor.

The invention is illustrated in the accompanying drawings as follows .Fig. 1 shows a central section of the device.

Fig. 2 a section on the line 2-2 in Fig. 1. Fig. 3 a section of a fragment of the parts shown in Fig. 1 with a different position of the mechanism.

Fig. 4 a front elevation of a portion of the resisting fan.

1 marks the frame, 2 a portion of a mounting ordinarily a part of the engine bed, and 3 a drive shaft ordinarily getting its motion from a device to be controlled such as an engine. The shaft 3 is journaledin bearings 4 in the frame. It is provided with a bev-` elled pinion 5 at its upper end driving a bevelled pinion 6. The bevelled pinion 6' is mounted on a sleeve-shaped driving shaft 7. The shaft 7 is mounted in bearings 8 in the frame 1. A spring driving head 9 is fixed on the shaft 7. A convenientv manner of mounting it is to provide the shaft 7 with a shoulder 10 against which the inner ring 11 of the bearing 8 abuts. The inner hub of the spring driving head 9 is clamped between the ring 11 and a clamp nut 12 on the end of the shaft 7 Y A spring 13 is secured to the head 9. Itis preferably formed of flatV spring material and wound so that the coils will nest one within the other. The larger end of the spring is secured to a driven head 14 which is fixed on a sliding head 15. The head 15 is slidingly mounted on a shaft 16. A spline 17 is secured in the head 15 and operates in a groove 18 in the shaft, thus locking the head 15 against rotation on the shaft 16 but permitting it to slide thereon. The

Y shaft 16 is carried by the bearing 19 within the shaftV 7 and a bearing 2O is arranged` in the extension 21 of the frame 1. A screw 22 projectsfrom the head 15 along the shaft16 and is engaged by a nut 6a in the shaft 7.

'The operation of the device sofar as describedis as follows Motion isf given to the shaft 7 from the shaft 3. VThis motion is communicated to the shaft 16 through the spring 13. The' rotary motion of the shaft 16 is resisted by the fan 16a mounted on the flange 16". Inasmuch as the driving of the fan is accomplished through the spring 13 the resistance of the fan is communicated to the spring and as this resistance increases a point is reached where the spring yields and under these conditions the shaft 7 has a rotative motion relatively to the head 15 and shaft 16. This relative rotative movement is made use of through the action of the screw 22 in the nut 6a. It will be observed that when this rotation takes place the screw 22 is moved axially through the action of the screw and this axial movement may be utilized for controlling the driving mechanism or other device as desired. As the drive shaft is given any particular speed lthis speed is necessarily communicated tothe'4 fan and 1s accompanied by a certain res1st ance. This resistance is communicated through the spring and the spring yields to a certain extent corresponding to this resistance. Consequently a certain speed will Vbe accompanied by a definiteposition of the head 15.

It is preferable in most ncases to give to the*4 spring a certain initial tension and this is accomplished by limiting the outward movement of the head. As soon as the head reaches the stop 15a no further rotative movement between the sleeve 7 and the head 15 can take place and consequently the unf winding v.of the spring is limited'to this po,-

sition. -This may be set at any point desired in the assembling of the device.

Itis also preferable to limit the extent to which the spring may be rotated inasmuch fanl maybe such as to `unduly strain the spring. This is accomplished in kthe present instance by the Vcontact ofthe `driven head 14 with the spring driving head 9 as as atvery high speeds the resistance ofthe clearly shown in Fig. 3. v Afterthis engagement takes place no added strain can be' dey liveredto the spring. n c

` trolling device.

Y In order to communicate the axial movement of the head 15 to a device to be controlled'I provide the groove23 in the head l5 in which is arranged a collar 24. It is provided with the usual projecting pins 25 which extend into slots in the forked arm 26. VIhe forked arm is fixed on a shaft 27. The shaft 27 extends without the case formed bythe extension 2l and is provided with an arm 28 Which'formsa means for communicating the movement ofthe con- Ths forms va very sensitive yet very positive control and one Ywhich is capable of sustaining a high speed outside'of the range of the governing action. In somel devices this is very desirable, in fact, necessary.' For this reason the yfan is preferable to centrifugal weights or similar devices where excessive speed might be dangerous. l

"What I claim as new is c In a speed sensitive controlling device, the combination of a fan; a driven shaft on which the f an. is y mounted bearings lfor said Vsha-ft; an externally screwfthreaded sleeve slidingly mounted on the shaft; aridriving shaft Ywithin Whichthe driven shaft extends ;V

my hand.

p iROBERTE METQALFE. 

